View source for Euphorbia chaetocalyx

{{Treatment/ID
|accepted_name=Euphorbia chaetocalyx
|accepted_authority=(Boissier) Tidestrom
|publications={{Treatment/Publication
|title=Proc. Biol. Soc. Wash.
|place=48: 40. 1935
|year=1935
}}
|common_names=Bristlecup sandmat
|basionyms={{Treatment/ID/Synonym
|name=Euphorbia fendleri var. chaetocalyx
|authority=Boissier in A. P. de Candolle and A. L. P. P. de Candolle
}}
|synonyms={{Treatment/ID/Synonym
|name=Chamaesyce chaetocalyx
|authority=(Boissier) Wooton & Standley
}}
|hierarchy=Euphorbiaceae;Euphorbia;Euphorbia sect. Anisophyllum;Euphorbia chaetocalyx
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Euphorbiaceae]]</div><div class="higher-taxon"><small>genus</small>[[Euphorbia]]</div><div class="higher-taxon"><small>section</small>[[Euphorbia sect. Anisophyllum]]</div><div class="higher-taxon"><small>species</small>[[Euphorbia chaetocalyx]]</div></div>
|volume=Volume 12
|mention_page=page 257, 264, 282, 267, 270, 282
|treatment_page=page 263
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Herbs,</b> perennial, with woody, thickened taproot. <b>Stems</b> usually erect, rarely slightly decumbent, often densely clustered from top of woody crown, 3–15 cm, glabrous. <b>Leaves</b> opposite; stipules distinct, narrowly linear, usually entire, 0.5–1 mm, glabrous; petiole 0.5–1 mm, glabrous; blade ovate to lanceolate or oblong- or linear-lanceolate, 3–11 × 0.8–3(–5) mm, base slightly asymmetric, short-tapered, occasionally one side slightly rounded, margins entire, apex acute or short-acuminate, surfaces glabrous; only midvein conspicuous. <b>Cyathia</b> solitary at distal nodes; peduncle 0.8–1.3 mm. <b>Involucre</b> campanulate to turbinate, 0.8–1.4 × 0.8–1 mm, glabrous; glands 4, yellow-brown to reddish, concave or convex, elliptic or oval, 0.2–0.4 × 0.4–0.6 mm; appendages absent or white, lanceolate-deltate to straplike, 0.2–1.1 × 0.2–0.9 mm, distal margin entire, crenate, or deeply cleft or divided. <b>Staminate</b> flowers 25–35. <b>Pistillate</b> flowers: ovary glabrous; styles 0.3–0.4 mm, 2-fid 1/2 length. <b>Capsules</b> depressed-ovoid to depressed-globose, 1.7–2.1 × 1.6–2.4 mm, glabrous; columella 1.2–1.8 mm. <b>Seeds</b> white, ovoid-pyramidal, prominently 4-angled in cross section, 1.6–2 × 1–1.2 mm, smooth to slightly wrinkled.</span><!--

-->{{Treatment/Body
|distribution=sw;sc United States;n Mexico.
|discussion=<p>Varieties 2 (2 in the flora).</p><!--
--><p><i>Euphorbia chaetocalyx</i> is similar to <i>E. fendleri</i> but can generally be distinguished from that species by its narrow, acute leaves and ± erect stems. Some authors have used the presence or absence and shape of the involucral gland appendages to help separate <i>E. chaetocalyx</i> from <i>E. fendleri</i>, but those characters appear highly variable and of little taxonomic utility. Some individuals from western Texas (Culberson and El Paso counties) and southern New Mexico appear intermediate with <i>E. fendleri</i>. The specific epithet of <i>E. chaetocalyx</i> refers to the bristly perianthlike segments that subtend the ovary, but these structures are found intermittently in both <i>E. chaetocalyx</i> and <i>E. fendleri</i>.</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Leaf blades ovate to lanceolate or oblong- or linear-lanceolate; involucral gland appendages absent or lanceolate-deltate, entire, crenate, or deeply cleft; widely distributed in Arizona, New Mexico, w Texas.
|[[Euphorbia chaetocalyx var. chaetocalyx|Euphorbia chaetocalyx var. chaetocalyx]]
|-id=key-0-1
|1
|Leaf blades narrowly-ovate to linear-lanceolate; involucral gland appendages straplike, divided into 3–5 linear segments; cliffs and rocks of Boquillas Canyon, sw Texas.
|[[Euphorbia chaetocalyx var. triligulata|Euphorbia chaetocalyx var. triligulata]]
|}
</div></div><!--

-->{{#Taxon:
name=Euphorbia chaetocalyx
|author=
|authority=(Boissier) Tidestrom
|rank=species
|parent rank=section
|synonyms=Chamaesyce chaetocalyx
|basionyms=Euphorbia fendleri var. chaetocalyx
|family=Euphorbiaceae
|distribution=sw;sc United States;n Mexico.
|reference=None
|publication title=Proc. Biol. Soc. Wash.
|publication year=1935
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/8f726806613d60c220dc4493de13607dd3150896/coarse_grained_fna_xml/V12/V12_102.xml
|genus=Euphorbia
|section=Euphorbia sect. Anisophyllum
|species=Euphorbia chaetocalyx
}}<!--

-->[[Category:Treatment]][[Category:Euphorbia sect. Anisophyllum]]